Linux: Use of Uninitialized Resource
CVE-2026-43291 is a high-severity use of uninitialized resource vulnerability in Linux, with a CVSS 3.1 base score of 8.3 out of 10. It can be exploited from the same local network by an unauthenticated attacker, without any action from a user. The record lists versions a24a8a582da4426b2042e510a1080df84083b51d, f5218426f765eee22e178df9c126d974792fb6a5, ad058a4317db7fdb3f09caa6ed536d24a62ce6a0 as the first without the flaw, so updating Linux to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.27% chance of exploitation within 30 days, which is low compared with other CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update Linux to a24a8a582da4426b2042e510a1080df84083b51d or f5218426f765eee22e178df9c126d974792fb6a5 or ad058a4317db7fdb3f09caa6ed536d24a62ce6a0 or 3b91160e9a91b5a2662875417dc42dc5b0bf03ea, whichever matches your release line, or a later version.
- Update Linux Kernel to 5.15.202 or 6.1.165 or 6.6.128 or 6.12.75, whichever matches your release line, or a later version.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Linux | Linux | 8fcc7315a10a84264e55bb65ede10f0af20a983f up to, but not including, a24a8a582da4426b2042e510a1080df84083b51d; bfdda0123dde406dbff62e7e9136037e97998a15 up to, but not including, f5218426f765eee22e178df9c126d974792fb6a5; 0ba68bea1e356f466ad29449938bea12f5f3711f up to, but not including, ad058a4317db7fdb3f09caa6ed536d24a62ce6a0; 74837bca0748763a77f77db47a0bdbe63b347628 up to, but not including, 3b91160e9a91b5a2662875417dc42dc5b0bf03ea; 9c328f54741bd5465ca1dc717c84c04242fac2e1 up to, but not including, c692db813a7e3b7c3c17d6e9a3ad2a018bf1142b; 9c328f54741bd5465ca1dc717c84c04242fac2e1 up to, but not including, 498fc5d0d650c77e87fcc73808d4f43240c21805; 9c328f54741bd5465ca1dc717c84c04242fac2e1 up to, but not including, 571dcbeb8e635182bb825ae758399831805693c2; c395d1e548cc68e84584ffa2e3ca9796a78bf7b9; and 6 more ranges | a24a8a582da4426b2042e510a1080df84083b51d, f5218426f765eee22e178df9c126d974792fb6a5, ad058a4317db7fdb3f09caa6ed536d24a62ce6a0, 3b91160e9a91b5a2662875417dc42dc5b0bf03ea, c692db813a7e3b7c3c17d6e9a3ad2a018bf1142b, 498fc5d0d650c77e87fcc73808d4f43240c21805 |
| Linux | Linux Kernel | 5.15.195 up to, but not including, 5.15.202; 6.1.156 up to, but not including, 6.1.165; 6.6.112 up to, but not including, 6.6.128; 6.12.53 up to, but not including, 6.12.75; 6.17.3 up to, but not including, 6.18; 6.18 up to, but not including, 6.18.16; 6.19 up to, but not including, 6.19.6 | 5.15.202, 6.1.165, 6.6.128, 6.12.75, 6.18, 6.18.16 |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- AdjacentThe attacker must be on the same local network segment.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- LowLimited modification of data is possible.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:H. Scored by CNA.
Official description
In the Linux kernel, the following vulnerability has been resolved: net: nfc: nci: Fix parameter validation for packet data Since commit 9c328f54741b ("net: nfc: nci: Add parameter validation for packet data") communication with nci nfc chips is not working any more. The mentioned commit tries to fix access of uninitialized data, but failed to understand that in some cases the data packet is of variable length and can therefore not be compared to the maximum packet length given by the sizeof(struct).
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Use of Uninitialized Resource
The product uses or accesses a resource that has not been initialized.
How developers prevent this class of flaw
- Explicitly initialize the resource before use. If this is performed through an API function or standard procedure, follow all required steps.
- Pay close attention to complex conditionals that affect initialization, since some branches might not perform the initialization.
- Avoid race conditions (CWE-362) during initialization routines.
More Use of Uninitialized Resource vulnerabilities (CWE-908)
Timeline
- CVE record published.
- Record last changed materially (score, affected products, status or references).
References
Patches and release notes
- git.kernel.org/stable/c/3b91160e9a91b5a2662875417dc42dc5b0bf03ea
- git.kernel.org/stable/c/498fc5d0d650c77e87fcc73808d4f43240c21805
- git.kernel.org/stable/c/571dcbeb8e635182bb825ae758399831805693c2
- git.kernel.org/stable/c/a24a8a582da4426b2042e510a1080df84083b51d
- git.kernel.org/stable/c/ad058a4317db7fdb3f09caa6ed536d24a62ce6a0
- git.kernel.org/stable/c/c692db813a7e3b7c3c17d6e9a3ad2a018bf1142b
- git.kernel.org/stable/c/f5218426f765eee22e178df9c126d974792fb6a5
Recent Use of Uninitialized Resource vulnerabilities
- 7.8 High severity
- 7.5 High severity
- 8.6 High severity
- 7.8 High severity
- 7.1 High severity
- 7.5 High severity
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